Copying device



COPYING DEVICE Original Filed Feb. 12, 1930 INVENTOR William C. Bokmerf).

ATTORNEY Patented on. 17, 1933 1,930,605

UNlTED STATES PATENT OFFICE COPYING DEVICE William C. Bohmert, Mamaroneck, N. Y.

- Application February 12, 1930, Serial No. 427,818

Renewed September 6, 1933 4 Claims. (Cl. 197126) This invention relates to copying devices and screws from the typewriter, lift the roll off the more particularly to such devices adapted to use machine and then slip the cylindrical copying on typewriters. device over the end and into central position.

The objects of the invention are, among others, Only one removal of the platen is required, it

to provide a copying device that can be quickly is obvious, both to remove a used device and to 60 attached to and detached from the platen of a insert a new one. The numerals land 2 inditypewriter, that produces areverse impression on cate in all the views the overlying edge and the back of a transparent copying sheet, that is the underlying edge respectively of a thin sheet low in cost and, although adapted for discard impregnated with carbon or copying ink of a when detached from the platen still possesses type that produces amaximum of copies adapted 66 such great copying longevity as to effect an apfor making a reverse impression upon the back preciable economy in typewriter manifolding, of a transparent overlying copying sheet. It is that is quickly installed on the platen without noted in Figures 1 and 2 that the terminating smudging of the copying material and without edge 1 overlies the edge 2 in a counterclockwise 5 smearing the fingers of the operator, that does direction as viewed from the right so that as the 70 not smear the side rolls or guides of the typecopying device is rolled through the platen supwriter when installed, that enhances the endurport of a typewriter any inadvertently unsecured ance of the platen surface, and that possesses part would not be torn or turned by the feed novel features of construction and relationship rolls to produce a copy blank and thereby render 2 of the component elements providing the forethe whole device useless. It will be noted later 75 going properties in the article and also anticithat I provide indices to insure the insertion of pating low manufacturing cost. the copying device so that the foregoingcondi- I am well aware that inventors have essayed tion always obtains.

contributions to the field of reverse copying upon After experimenting with a great number of 5 a transparent copying sheet in a typewriter. materials I have selected a 40-1b. Kraft paper The essential elements of low cost and adaptabilwhich I cut in sheets that are approximately the ity for quick, insertion and removal from the width of the platen and whose length is twice the copying position have heretofore been lacking. circumference of the platen cylinder for which Reference is made to the drawing which is a they are manufactured, or a multiple of this 30 Dart of this specification, in which measurement. The top edge 4 is then rolled 5 Figure l is a perspective view from the right under and after two turns the sheet terminates front of my copying device but with parts slightly in the same radial plane 6 in the opposite edges opening up from normal position to show the with a whole or continuous strip .5 inbetween.

construction more clearly, As shown in Figures 1 and 2 the top layer 3 is 5 Figure 2, is a right end view with the eleshown for the sake of illustration slightly bent 0 ments also opened up as in Figure l, away from the stip 5 and similarly the lower Figure 3 is a front view with the diametric layer 4 but in the completed tube as shown in scale reduced one-half, and Figure 3 the parts 3, 4, and 5 are snugly com- Fig. 4 is an end view showing the angular pressed together. The 40-lb. Kraft paper is" 40 bend in the strip 5 when in operative position tough and stiff but yet sufiiciently flexible to form 95 on the platen of a typewriter. a slight bend or angle from left to right as viewed Referring to the drawing for a view of the from the right permitting the top layer 3 termiprescnt embodiment of y invention, it is obnating in the radial plane 6 of the cylinder to lie served that my device is constructed in the snug against one side of the bend in strip 5 and form of a cylinder whose inner circumference the terminal end of lower lever 4 to lie snug m is approximately the same as that of the ciragainst the opposite side of the bend lying incumference of a typewriter platen. Where there between in part 5 lying inbetween. It is noted is variation in the sizes of platens the only in Figures 1 and 2 as viewed from the right that change required to make my invention adaptable the terminal edge of the top layer 3 is in a directo such typewriters is to make the measurements tion counterclockwise and in the same direction of the components of my copying device conas the terminal edge 1 of the copying surface so form with the circumference of the particular that in its normal operation position the edge platen or machine model platen on which my of part 3 in plane 6 is always to the rear as device is to be used. In installing the device passed through a typewriter in operation so that it is simply necessary to remove one or two the feed rolls tend to press it toward the part 5 the tube and to hold the edge snug against the angled surface of 5 between the top edge and the bottom edge in the radial plane 6. By this construction of my device I provide a stiff and durable supporting cylindrical base for my copying surface without having a longitudinal surface ridge which if present would tend to tear or break the thin copying surface or to blank the copy by the incidence of the typewriter type upon a line in which there was no backing surface. By the construction above described in practice there is no edge of sufficient prominence to affect the production of a clear copy or to cause any breaking or tearing of the copying surface. By reference to Figures 1 and 2 it is also clear that the juncture longitudinal line of terminal edges 1 and 2 of the copying sheet is circumferentially removed from the radial plane 6. As shown in Figures 1 and 3 I provide as indices ininserting my copying device on the typewriter platen in such a position as to get the beneficial results of my construction in the fullest degree as above set forth "the word Right imprinted on the e: posed side strip '1 of the surface 3. As shown in Figure 3 there is another strip I on the opposite side provided by cutting the carbon or copying sheet of less width than the sheet 5' and centering the carbon or copying sheet on the sheet 5. These strips '7 are of sufiicient width to provide a noncopying surface by whichthe copying device may be picked up in the fingers without smearing them with the copying material and also they prevent the copying material from smudging the side guides or rolls of the typewriter a condition which would practically inhibit the use of my device. The component elements of my device are preferably secured together by a good adhesive material.

The longevity of my device has been'proven to be many multiples of the period of longevity of a carbon sheet and therefore my invention effects,

besides a great saving in the time of the operative, also a considerable economy in the cost of materials used. This economy is also augmented by an increase in the life of the platen surface of the typewriter. My stiff backing surface absorbs the usual row of indentations in the rubber platen and after using many of my devices the platen surface shows no sign of use at all.

In order to facilitate the removal of a used tube from the platen I provide a notch or cutaway portion 8 in the upper of the two layers of the paper for the easy insertion of a knife-blade point or other instrument for cutting or ripping lengthwise, preferably at theend of a longitudinal line free of the adhesive or gum used to secure the two portions of paper together.

Having now particularly described and pointed out the construction and use of a preferred embodiment of my invention I do not choose to limit myself except as in the appended claims.

I claim:-

1. As an article of manufacture, a copying device adapted to overlie a typewriter platen and to produce a reverse impression of typed matter on the reverse side of a copying sheet, comprising a sheet of stiff fibrous material sufficiently heavy to support a large number of type impacts, made into a cylinder and said sheet having a length slightly less than twice the circumference of the platen, or a multiple thereof whereby the end edges will not overlap to form a bulge or ridge across the cylinder, and a copying material superimposed thereon.

2. As an article of manufacture, a copying device adapted to overlie a typewriter platen and to produce a reverse impression of typed matter on the reverse side of a copying sheet, comprising a sheet of stiff fibrous material sufliciently heavy to support a large number of type impacts, made into a cylinder and said sheet having a length slightly less than twice the circumference of the platen, or a multiple thereof whereby the end edges will not overlap to form a bulge or ridge across the cylinder, and a copying sheet having a length slightly greater than that of the circumference of the platen secured to said cylinder.

3. As an article of manufacture, a quick detachable copying tube adapted to snugly fit and cover a typewriter platen and adapted to produce a reverse impression of typed material on the back of a copying sheet, comprising a cylinder formed of two plies of stiff pliable paperthe end edges of the inner and outer plies terminating a slight distance apart circumferentially of the cylinder whereby that part lying intermediate the end edges will be bent across the end edge of the inner ply to provide a recess into which the end edge of the outer ply will seat.

4. As an article of manufacture, a quick detachable copying tube adapted to snugly fit and cover a typewriter platen and adapted to produce a reverse impression of typed material on the back of a copying sheet, comprising a cylin-.

der formed of two plies of stiff pliable paper the end edges of the inner and outer plies terminating a slight distance apart circumferentially of the cylinder whereby that part lying intermediate the end edges will be bent across the end edge of the inner ply to provide a recess into which the end edge of the outer ply will seat, and a thin carbon sheet on said cylinder and overlapping on a line removed from said end edges.

WILLIAM C. BOHMERT. 

